1 Features

• Low output 1/f noise < 20μVRMS (100Hz to

100kHz)

• Low output voltage ripple < 10μVRMS after ferrite

bead

• High PSRR of > 65dB (up to 100kHz)

• 2.2MHz, 1.4MHz, or 1.0MHz fixed frequency peak

current mode control

• Synchronizable with external clock (optional)

• Integrated loop compensation supports ferrite

bead for second stage L-C filter with 30dB

attenuation (optional)

• Spread spectrum modulation (optional)

• 3.0V to 17V input voltage range

• 0.8V to 5.5V output voltage range

• 25mΩ/7mΩ RDSon

• Output voltage accuracy of ±1% over temperature

• Precise enable input allows

– User-defined undervoltage lockout

– Exact sequencing

• Adjustable soft start

• Power-good output

• Output discharge (optional)

• –40°C to 125°C junction temperature range

• 4.0mm × 4.7mm × 3.0mm QFN

• Create a custom design using the TPSM8291x

with the WEBENCH® Power Designer

2 Applications

• Telecom infrastructure

• Test and measurement

• Aerospace and defense (radar, avionics)

• Medical

3 Description

The TPSM8291x devices are a family of highefficiency,

low noise, and low ripple current mode

synchronous buck modules. The devices are

designed for noise sensitive applications that normally

use an LDO for post regulation such as high-speed

ADCs, clock and jitter cleaner, serializer, de-serializer,

and radar applications.

To reduce the output voltage ripple, the device

loop compensation is designed to operate with an

optional second-stage ferrite bead L-C filter. Lowfrequency

noise levels, similar to a low-noise LDO,

are further achieved by filtering the internal voltage

reference with a capacitor connected to the NR/SS

pin. Combined, these features allow for an output

voltage ripple below 10μVRMS.

The device operates at a fixed switching frequency of

2.2MHz, 1.4MHz, or 1MHz, and can be synchronized

to an external clock. An optional spread spectrum

modulation scheme spreads the DC/DC switching

frequency over a wider span, which lowers the mixing

spurs.